NYT Researchers have devised a new tool for discerning between naturally occurring viral outbreaks and those resulting from lab accidents. The Covid pandemic was an extraordinary moment in history. Starting at the end of 2019, a virus new to science swept across the planet, killed more than 25 million people and caused trillions of dollars in economic damage.
But as outbreaks go, Covid was pretty ordinary, a new study finds.
Scientists compared seven viral outbreaks that occurred in recent decades, including epidemics of Covid, Ebola and influenza. For the most part, the researchers found, the outbreaks were not preceded by any unusual genetic changes in the viruses. In all but one case, in 1977, the viruses circulated in animals and gained the ability to spread to and among people only by unfortunate coincidence.
“We see that time and again,” said Joel Wertheim, a virologist at the University of California San Diego. He and his colleagues published the study on Friday in the journal Cell.